Smell nanobiosensors: Hybrid systems based on the electrical response to odorant capture. Theory and experiment

Mammalian olfactory system is the archetype of sensor device. Its complexity resides both in the odorant mechanism of capture by the single olfactory receptor (OR) and in the spatial organization and codification of information so to produce an unique profile for each odorant. Our aim is to partially mimick this system to produce a biosensor on nanometric scale. The active part of the device is constituted of few nanosome containing specific ORs. The nanosome is interfaced with nano-electrodes and the odorant capture is transduced into an electric signal. Specifically, the electrical response is correlated with the conformational change that a single OR undergoes when it captures a specific odorant molecule. An array of nanodevices should be able to produce specific response profiles. In this paper we present a possible theoretical framework in which the experimental results should be embedded. It consists of the description of the protein in terms of an impedance network able to simulate the electrical characteristics associated with the protein topology.